1. Field of the Invention
This invention relates to an apparatus and method for fuel combustion. More particularly, the invention comprises an apparatus which can be used either as an open-flame torch, or which can be used as a soldering tool, capable of generating high temperatures. The apparatus includes valve assemblies that substantially eliminate liquid fuel emission from the device, and that also provide other safety features. The device is lightweight, portable, and includes means to refill its fuel chamber. The device provides efficient and safe fuel combustion at any orientation.
2. Description of the Prior Art
Portable, fuel combustion devices, such as gas lighters, are widely known. These devices typically include a fuel cartridge or canister for containing pressurized fuel, and appropriate valve assemblies for releasing the fuel in a controlled manner. Such gas lighters are disclosed in U.S. Pat. No. 4,181,493 to Piffath, et al., U.S. Pat. No. 3,820,941 to Blank, and U.S. Pat. No. 3,523,006 to Piffath, et al. These devices include relatively simple and inefficient gas regulating and valve assemblies, and are not generally suitable for commercial applications. They are generally suitable only as providing a simple ignition source.
Other devices, however, have been developed to provide for fuel combustion for use in more specific applications, such as pipe fitting. These devices generally include a relatively large butane gas tank with a removable valve assembly having an elongated nozzle. Recently, various other devices have been developed, which accomplish controlled fuel combustion for use in a soldering tool. For example, U.S. Pat. No. 4,785,793, and European Patent No. 118,282, both to Oglesby. et al., disclose a portable soldering tool having a fuel cartridge and valve means for regulating the emission and combustion of the fuel. A soldering tip is carried by the device, and the sole application of the device is as a soldering tool. The Oglesby patents are directed specifically to a heat conductive support member included within the soldering tip for solely supporting the soldering tip.
These prior art devices generally have been found to be both inefficient in the delivery and combustion of fuel, and, at times, unsafe. A common problem with such devices is uneven burning or "flame up" caused by liquid fuel, such as liquid butane, entering the combustion zone. This is an extremely unsafe condition, and usually occurs when the device is pointed downwardly or jarred. Also, the control valve mechanisms on these prior art devices allow fuel to be delivered to the combustion zone in a "burst" when the valve is first opened. U.S. No. 4,133,301 to Fugiwara, discloses another gas combustion apparatus comprising a soldering tool. This device includes an arrangement of gas inlet lines and an ignition circuit, and is comparatively more complex and cumbersome than many other, portable devices.